[CHARGE-PUMP CIRCUITRY]
A charge-pump circuitry which receives an external voltage source to generate a target voltage is provided. The charge-pump circuitry comprises a voltage multiplier module and a voltage difference generating circuitry. Wherein, a first input terminal of the voltage multiplier module receives the external voltage source, and the voltage multiplier module generates a multiplied-voltage according to the external voltage source. The voltage potential of the multiplied-voltage is a predetermined times of the voltage potential of the external voltage source. The voltage difference generating circuitry generates a correcting voltage which is input to a second input terminal of the voltage multiplier module. The voltage potential of the correcting voltage is the potential difference between the target voltage and the multiplied-voltage.
This application claims the priority benefit of Taiwan application serial no. 92136375, filed Dec. 22, 2003.
BACKGROUND OF INVENTION1. Field of the Invention
The present invention relates to a charge-pump circuitry, and more particularly, to a charge-pump circuitry which directly outputs a target voltage.
2. Description of the Related Art
It is common that a system comprises multiple ICs which provide different functions, and some IC can operate normally only under a voltage potential higher than the external voltage source provided to the system. Therefore, it is common that the system uses a charge-pump circuitry to pull up the voltage potential of the external voltage source to a voltage potential required by these special ICs for supporting the normal operation of these ICs.
Referring to
Referring to
In summary, the conventional regulated charge-pump circuitry uses a voltage multiplier module to pull up an external voltage source first, and the pulled-up voltage is then sent to a voltage regulator for generating a target voltage.
SUMMARY OF INVENTIONTherefore, it is an object of the present invention to provide a charge-pump circuitry, which generates a target voltage directly from its output terminal without passing through a voltage regulator.
In order to achieve the object mentioned above and others, a charge-pump circuitry which receives an external voltage source to generate a target voltage is provided by the present invention. The charge-pump circuitry of the present invention comprises a voltage multiplier module, a voltage difference generating circuitry, and a first capacitor. Wherein, the voltage multiplier module comprises an input terminal and an output terminal, and its first input terminal receives an external voltage source. The voltage multiplier module generates a multiplied-voltage according to the external voltage source, and the voltage potential of the multiplied-voltage is a predetermined times of the voltage potential of the external voltage source. In addition, the voltage difference generating circuitry generates a correcting voltage, which is sent to a terminal on the output terminal side of the voltage multiplier module. The voltage potential of the correcting voltage is the potential difference between the target voltage and the multiplied-voltage. One terminal of the first capacitor mentioned above electrically couples to an output terminal of the voltage multiplier module, and the other terminal of the first capacitor is grounded. The voltage multiplier module adds a voltage potential of the multiplied-voltage to a voltage potential of the correcting voltage, and sends a voltage of the summation result to the first capacitor from its output terminal.
The voltage difference generating circuitry comprises an operational amplifier, a first resistor, a second resistor, and a third resistor. The operational amplifier comprises a negative signal input terminal, a positive signal input terminal, and an output terminal. Wherein, its positive signal input terminal receives a reference voltage, and its output terminal electrically couples to a second input terminal of the voltage multiplier module. One terminal of the first resistor electrically couples to the negative signal input terminal of the operational amplifier, and the other terminal of the first resistor receives an external voltage source. Similarly, one terminal of the second resistor electrically couples to the negative signal input terminal of the operational amplifier, and the other terminal of the second resistor is grounded. In addition, one terminal of the third resistor electrically couples to the negative signal input terminal of the operational amplifier, and the other terminal of the third resistor electrically couples to the output terminal of the operational amplifier.
In addition, the voltage multiplier module comprises a first switch circuit, a second switch circuit, and a second capacitor. Wherein, the first switch circuit comprises a 1st terminal, a 2nd terminal, a 3rd terminal, and a 4th terminal. The 1st terminal receives the external voltage source, and the 2nd terminal is grounded. One terminal of the second capacitor electrically couples to the 3rd terminal of the first switch circuit, and the other terminal electrically couples to the 4th terminal of the first switch circuit. Similarly, the second switch circuit comprises a 5th terminal, a 6th terminal, a 7th terminal, and an 8th terminal. The 5th terminal electrically couples to the 3rd terminal of the first switch circuit, the 6th terminal electrically couples to the 4th terminal of the first switch circuit, and the 7th and 8th terminals electrically couple to the output terminals of the voltage multiplier module. In summary, the function of the first switch circuit is to determine whether to have the external voltage source pass through to charge the second capacitor. The second switch circuit is used to determine whether to have the target voltage pass through to charge the first capacitor.
A summation of a potential stored by the second capacitor and a potential of the correcting voltage is the voltage potential of the target voltage mentioned above.
The first switch circuit comprises a first dual port switch and a second dual port switch, wherein one terminal of the first dual port switch electrically couples to the 1st terminal of the first switch circuit, and the other terminal of the first dual port switch electrically couples to the 3rd of the first switch circuit. One terminal of the second dual port switch electrically couples to the 2nd terminal of the first switch circuit, and the other terminal of the second dual port switch electrically couples to the 4th terminal of the first switch circuit. Therefore, the first and second dual port switches are used to determine whether to have the external voltage source pass through to charge the second capacitor.
Similarly, the second switch circuit comprises a third dual port switch and a fourth dual port switch, wherein one terminal of the third dual port switch electrically couples to the 5th terminal of the second switch circuit, and the other terminal of the third dual port switch electrically couples to the 7th terminal of the second switch circuit. One terminal of the fourth dual port switch electrically couples to the 6th terminal of the second switch circuit, and the other terminal of the fourth dual port switch electrically couples to the 8th terminal of the second switch circuit. Therefore, the third and fourth dual port switches are used to determine whether to have the correcting voltage pass through to charge the first capacitor.
Wherein, the “turn-on” and “turn-off” cycles of the first dual port switch and the second dual port switch is referred as a first clock cycle, the “turn-on” and “turn-off” cycles of the third dual port switch is referred as a second clock cycle, and the “turn-on” and “turn-off” cycles of the fourth dual port switch is referred as a third clock cycle. During the duty cycle of the first clock cycle, the second clock cycle, and the third clock cycle, the first dual port switch, the second dual port switch, the third dual port switch, and the fourth dual port switch are all turned on.
The duty cycle of the first clock cycle is not overlapped with the duty cycle of the second clock cycle, and the duty cycle of the first clock cycle is not overlapped with the duty cycle of the third clock cycle, neither. In addition, the duty cycle of the third clock cycle leads the duty cycle of the second clock cycle a certain period of time.
According to another aspect of the present invention, the charge-pump circuitry of the present invention provides a different type of the voltage multiplier module. Wherein, the first switch circuit still comprises a first dual port switch and a second dual port switch. One terminal of the first dual port switch electrically couples to the 1st terminal of the first switch circuit, and the other terminal of the first dual port switch electrically couples to the 3rd terminal of the first switch circuit. One terminal of the second dual port switch electrically couples to the 2nd terminal of the first switch circuit, and the other terminal of the second dual port switch electrically couples to the 6th terminal of the first switch circuit. Similarly, the first and second dual port switches are used to determine whether to have the external voltage source pass through to charge the second capacitor.
In addition, the second switch circuit also comprises a third dual port switch and a fourth dual port switch. One terminal of the third dual port switch electrically couples to the 5th terminal of the second switch circuit, and the other terminal of the third dual port switch electrically couples to the 7th terminal of the second switch circuit. One terminal of the fourth dual port switch electrically couples to the 4th terminal of the second switch circuit, and the other terminal of the second dual port switch electrically couples to the 8th terminal of the second switch circuit. Similarly, the third and fourth dual port switches are used to determine whether to have the correcting voltage pass through to charge the first capacitor.
Wherein, the “turn-on” and “turn-off” cycles of the first dual port switch and the second dual port switch is referred as a first clock cycle, the “turn-on” and “turn-off” cycles of the third dual port switch is referred as a second clock cycle, and the “turn-on” and “turn-off” cycles of the fourth dual port switch is referred as a third clock cycle. During the duty cycle of the first clock cycle, the second clock cycle, and the third clock cycle, the first dual port switch, the second dual port switch, the third dual port switch, and the fourth dual port switch are all turned on.
The duty cycle of the first clock cycle is not overlapped with the duty cycle of the second clock cycle, and the duty cycle of the first clock cycle is not overlapped with the duty cycle of the third clock cycle, neither. In addition, the duty cycle of the second clock cycle leads the duty cycle of the third clock cycle a certain period of time.
In summary, the charge-pump circuitry of the present invention pulls up the external voltage source to a predetermined times of voltage potential, and adds the pulled-up voltage to a correcting voltage for generating a target voltage directly without having to pass through a voltage regulator. In the present invention, if all elements are in ideal condition, the efficiency of the charge-pump circuitry of the present invention is up to 100%.
BRIEF DESCRIPTION OF DRAWINGSThe accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention.
Referring to
It is expected in the charge-pump circuitry of the present invention that the voltage multiplier module can generate a potential of multiplied-voltage V2 on the output terminal 23 according to a potential difference between the external voltage source VDD and the ground voltage, and a voltage potential of the correcting voltage V1 generated by the voltage difference generating circuitry 220 is added to it, so as to finally obtain a desired target voltage Vtarget.
Referring to
Meanwhile, if the resistance of the first resistor R1 is designed to be equal to the resistance of the third resistor R3, the equation (1) becomes:
If the first resistor R1 and the second resistor R2 are modified as Vref(2 R2+R1)/R2=Vtarget, the equation (2) becomes:
V1=V|arg s|−VDD
Accordingly, the correcting voltage V1 is obtained, and it is sent to the voltage multiplier module 210 in
To be more specific, the first switch circuit 310 is mainly composed of a first dual port switch 31 and a second dual port switch 33. One terminal of the first dual port switch 31 electrically couples to one terminal 25a in the input terminal 25 of the voltage multiplier module 210, and the other terminal of the first dual port switch 31 electrically couples to the 3rd terminal 31a of the first switch circuit 310. In addition, one terminal of the second dual port switch 33 electrically couples to the other terminal 25b in the input terminal 25 of the voltage multiplier module 210, and the other terminal of the second dual port switch 33 electrically couples to the 4th terminal 33a of the first switch circuit 310. The “turn-on” and “turn-off” cycles of the first dual port switch 31 is synchronized with the “turn-on” and “turn-off” cycles of the second dual port switch 33 and referred as a first clock cycle herein. During the duty cycle of the first clock cycle, the first dual port switch 31 and the second dual port switch 33 are turned on.
Referring to
Wherein, the “turn-on” and “turn-off” cycles of the third dual port switch 35 is referred as a second clock cycle, and the “turn-on” and “turn-off” cycles of the fourth dual port switch 37 is referred as a third clock cycle. During the duty cycle of the second clock cycle and the third clock cycle, the third dual port switch 35 and the fourth dual port switch 37 are turned on. In the present embodiment, the duty cycle of the third clock cycle leads the duty cycle of the second clock cycle a certain period of time, and the duty cycle of the second clock cycle and the third clock cycle is not overlapped with the duty cycle of the first clock cycle. In other words, when the first dual port switch 31 and the second dual port switch 33 are turned on, the third dual port switch 35 and the fourth dual port switch 37 are turned off. In addition, when the fourth dual port switch 37 is turned on, the first dual port switch 31 and the second dual port switch 33 are turned off, and the third dual port switch 35 is turned on only after the fourth dual port switch 37 has been turned on for a certain period of time and before the fourth dual port switch 37 is turned off.
Referring to
The embodiments shown in
In summary, the charge-pump circuitry of the present invention adds the multiplied-voltage to the correcting voltage for directly generating a desired target voltage without passing through the voltage regulator. Therefore, there is no electrical energy loss. If all the elements in the present invention are in ideal condition, the electrical energy used by it is up to 100%. Even in the physical environment, the efficiency of the present invention is still very high.
Although the invention has been described with reference to a particular embodiment thereof, it will be apparent to one of the ordinary skill in the art that modifications to the described embodiment may be made without departing from the spirit of the invention. Accordingly, the scope of the invention will be defined by the attached claims not by the above detailed description.
Claims
1. A charge-pump circuitry, receiving an external voltage source to generate a target voltage, comprising:
- a voltage multiplier module, comprising an input terminal and an output terminal, wherein the output terminal comprises a first terminal and a second terminal, the input terminal receives the external voltage source, the voltage multiplier module generates a multiplied-voltage on the first terminal and the second terminal according to the external voltage source, and the multiplied-voltage is a predetermined times of a voltage potential of the external voltage source;
- a voltage difference generating circuitry for generating a correcting voltage, wherein an output terminal of the voltage difference generating circuitry electrically couples to the second terminal in the output terminal of the voltage multiplier module, and a voltage potential of the correcting voltage is a potential difference between the target voltage and the multiplied-voltage; and
- a first capacitor, wherein one terminal of the first capacitor electrically couples to the first terminal in the output terminal of the voltage multiplier module, and the other terminal is grounded.
2. The charge-pump circuitry of claim 1, wherein the voltage difference generating circuitry comprises:
- an operational amplifier, comprising an negative signal input terminal, a positive signal input terminal, and an output terminal, wherein the positive signal input terminal receives a reference voltage, and the output terminal electrically couples to the second input terminal;
- a first resistor, wherein one terminal of the first resistor electrically couples to the negative signal input terminal, and the other terminal receives the external voltage source;
- a second resistor, wherein one terminal of the second resistor electrically couples to the negative signal input terminal, and the other terminal is grounded; and
- a third resistor, wherein one terminal of the third resistor electrically couples to the negative signal input terminal, and the other terminal electrically couples to the output terminal.
3. The charge-pump circuitry of claim 1, wherein the voltage multiplier module comprises:
- a first switch circuit, comprising a 1st terminal, a 2nd terminal, a 3rd terminal, and a 4th terminal, wherein the 1st terminal receives the external voltage source, and the 2nd terminal is grounded;
- a second capacitor, wherein one terminal of the second capacitor electrically couples to the 3rd terminal, and the other terminal electrically couples to the 4th terminal; and
- a second switch circuit, comprising a 5th terminal, a 6th terminal, a 7th terminal, and an 8th terminal, wherein the 5th terminal electrically couples to the 3rd terminal, the 6th terminal electrically couples to the 4th terminal, and the 7th terminal and the 8th terminal are the output terminal;
- wherein, the first switch circuit determines whether to have the external voltage source pass through to charge the second capacitor, and the second switch circuit determines whether to have the target voltage pass through to charge the first capacitor.
4. The charge-pump circuitry of claim 3, wherein the voltage potential of the target voltage is a summation of a potential stored in the second capacitor and the voltage potential of the correcting voltage.
5. The charge-pump circuitry of claim 4, wherein the first switch circuit comprises:
- a first dual port switch, wherein one terminal of the first dual port switch is the 1st terminal, and the other terminal of the first dual port switch is the 3rd terminal; and
- a second dual port switch, wherein one terminal of the second dual port switch is the 2nd terminal, the other terminal of the second dual port switch is the 4th terminal, and the first dual port switch and the second dual port switch determine whether to have the external voltage source pass through to charge the second capacitor.
6. The charge-pump circuitry of claim 5, wherein the second switch circuit comprises:
- a third dual port switch, wherein one terminal of the third dual port switch is the 5th terminal, and the other terminal of the third dual port switch is the 7th terminal; and
- a fourth dual port switch, wherein one terminal of the fourth dual port switch is the 6th terminal, the other terminal of the fourth dual port switch is the 8th terminal, and the third dual port switch and the fourth dual port switch determine whether to have the target voltage source pass through to charge the first capacitor.
7. The charge-pump circuitry of claim 6, wherein a “turn-on” and “turn-off” cycle of the first dual port switch and the second dual port switch is referred as a first clock cycle, a “turn-on” and “turn-off” cycle of the third dual port switch is referred as a second clock cycle, a “turn-on” and “turn-off” cycle of the fourth dual port switch is referred as a third clock cycle, and during a duty cycle of the first clock cycle, the second clock cycle, and the third clock cycle, the first dual port switch, the second dual port switch, the third dual port switch, and the fourth dual port switch are turned on.
8. The charge-pump circuitry of claim 7, wherein the duty cycle of the first clock cycle is not overlapped with the duty cycle of the second clock cycle, and the duty cycle of the first clock cycle is not overlapped with the duty cycle of the third clock cycle, neither.
9. The charge-pump circuitry of claim 8, wherein the duty cycle of the third clock cycle leads the duty cycle of the second clock cycle a certain period of time.
10. The charge-pump circuitry of claim 4, wherein the first switch circuit comprises:
- a first dual port switch, wherein one terminal of the first dual port switch is the 1st terminal, and the other terminal of the first dual port switch is the 3rd terminal; and
- a second dual port switch, wherein one terminal of the second dual port switch is the 2nd terminal, the other terminal of the second dual port switch is the 6th terminal, and the first dual port switch and the second dual port switch determine whether to have the external voltage source pass through to charge the second capacitor.
11. The charge-pump circuitry of claim 10, wherein the second switch circuit comprises:
- a third dual port switch, wherein one terminal of the third dual port switch is the 5th terminal, and the other terminal of the third dual port switch is the 7th terminal; and
- a fourth dual port switch, wherein one terminal of the fourth dual port switch is the 4th terminal, the other terminal of the fourth dual port switch is the 8th terminal, and the third dual port switch and the fourth dual port switch determine whether to have the target voltage source pass through to charge the first capacitor.
12. The charge-pump circuitry of claim 11, wherein a “turn-on” and “turn-off” cycle of the first dual port switch and the second dual port switch is referred as a first clock cycle, a “turn-on” and “turn-off” cycle of the third dual port switch is referred as a second clock cycle, a “turn-on” and “turn-off” cycle of the fourth dual port switch is referred as a third clock cycle, and during a duty cycle of the first clock cycle, the second clock cycle, and the third clock cycle, the first dual port switch, the second dual port switch, the third dual port switch, and the fourth dual port switch are turned on.
13. The charge-pump circuitry of claim 12, wherein the duty cycle of the first clock cycle is not overlapped with the duty cycle of the second clock cycle, and the duty cycle of the first clock cycle is not overlapped with the duty cycle of the third clock cycle, neither.
14. The charge-pump circuitry of claim 13, wherein the duty cycle of the second clock cycle leads the duty cycle of the third clock cycle a certain period of time.
Type: Application
Filed: May 19, 2004
Publication Date: Jun 23, 2005
Patent Grant number: 7042742
Inventor: Meng-Jyh Lin (Hsinchu City)
Application Number: 10/709,638